NEWBURGH, N.Y. - Sunday morning in this small, Hudson Valley city: More
than 1,000 parishioners, most from Mexico, pack Spanish-language Masses at
St. Patrick's Catholic Church.

Afterward, many families flock to El Azteca for its authentic tacos. If
somebody needs a ride home, there are at least a dozen local taxi companies
catering to newcomers born in the Mexican states of Puebla and Jalisco.

New residents from Mexico have, in the last four years, opened dozens of
businesses that have begun to reinvigorate the ailing downtown district;
they are the region's fastest growing community.

It's the same story elsewhere in the Northeast. Like the other parts of the
country before it, the region is finally starting to see the impact of
Mexican migration.

New communities of Mexicans have arrived to fill farm, construction and
domestic jobs, government data show. Population growth in states such as
Pennsylvania, Massachusetts and Connecticut would be considerably slower if
not for the newcomers, who are steadily bringing about the region's biggest
demographic shift in generations.

And while the change has brought new vitality to some places, it has also
created tension.

Logical explanation

Rodolfo O. de la Garza, a sociologist at Columbia University, says
it's natural that Mexico is - and will be - the main source of Hispanic
migration to the United States.

"Mexico is right there and Mexico is so big," he said. "They're not going to
become the dominant group in the Northeast, but they're going to be
increasingly important numerically."

Sixty miles north of New York City, Newburgh has historically had a small
Puerto Rican community. But these days Mexicans drawn to farm work in area
apple orchards, dairy farms and factories far outnumber Puerto Ricans,
demographers say.

In 2000, the city's 4,500 Mexicans represented half of all its Latinos;
today, Mexicans are two-thirds of that group, demographers estimate.

"I've seen (Mexicans) grow from a very small quiet-type community to a very
large population, and it continues to grow," said Richard Rivera, president
of Latinos Unidos, a local advocacy group.

Nationally, most Mexican-born residents have long been concentrated in
California and Texas, said Jeffrey S. Passel, a demographer with the Pew
Hispanic Center in Washington, D.C. "If you go back 15 or 20 years, there
weren't very many Mexicans outside of core settlement areas of the
Southwestern states and the Chicago area."

Many move directly now

In the early 1990s, he said, California's ailing economy and rising
anti-immigrant sentiments pushed some Mexican immigrants into new places
with abundant jobs such as North Carolina, Georgia and New York City.

As new immigrants kept arriving - peaking at more than 600,000 a year around
1999 or 2000 - many joined friends or family resettled in the new areas.
Tens of thousands went straight from the Mexican state of Michoacan to
meatpacking jobs in Tar Heel, N.C., and from Puebla to work in restaurants
and private homes in Manhattan.

Another factor fueling the influx was the nation's widespread real-estate
boom, which drove steady growth in construction jobs. Last year, nearly one
in five foreign-born Hispanics was a construction worker, Pew data show.

Roberto Calderin moved to Orange County, which includes Newburgh, in 1996
and has seen the changes.

"I went to a restaurant, an Italian restaurant, the other day, and I started
horsing around with one of the busboys. I said, 'How many Mexicanos
you got back there cooking?' He said, 'They're all Mexicans.' "

Small but rapidly expanding Mexican communities also are now in East Boston;
Burlington, Vt.; Central Falls and Providence, R.I., said Martha Montero-Seiburth,
a professor at the University of Massachusetts-Boston.

In Maine, where most immigrants pick apples or blueberries or work on dairy
farms, census estimates counted 4,419 Mexicans in 2003, up 48 percent from
2000.